The Nazgul framework performs GRB localization via fitting non-parametric models to their data time-series and computing the the time delay between them. It is built on Stan (ascl:1801.003) and implements a parallel version of non-stationary Random Fourier Features. This avoids using heuristic methods, such as cross-correlation, which do not have a self-consistent statistical model. Satellites throughout the Sol system observe gamma-ray bursts at different times due to the finite speed of light, creating a time delay in their observed light curves. The time delay can be used to triangulate the gamma-ray burst position on the sky; these triangulations create annuli or rings on the sky. Nazgul searches for these annuli so that in the darkness, it can bind them to a location on the sky.